1. Field of the Invention
The present application is directed to the field of robotics and more particularly, to the manipulation of bulky and irregular objects such as bottles through the use of robotic manipulation.
2. Description of Related Art
There is a need in bottle handling industries to load bottles, such as full 5 gallon or 3 gallon water bottles into racks or crates. In the past such bottles were loaded manually. Recently, rack loaders using chains having inserts or flights in an elevator configuration have also been used. In such a configuration, bottles are pushed out of the elevator into the rack using, for example, air cylinders. While handling bottles in such a manner has limited efficiency, moving bottles using an elevator lacks the requisite flexibility and cannot be used for unloading.
Most bottles, such as, for example, commercial water bottles are irregularly shaped and difficult to grasp. While it is preferred to grasp the bottle by its neck only during normal upright handling, the weight of most bottles makes neck grasping tenuous during loading and unloading operations since bottles must necessarily be tilted. Any changes in orientation of the bottle from its vertical axis give rise to disproportionate torque forces generated from the body of the bottle on the neck. Such forces are difficult to manage even in a robotic context. Some are developing very complex mechanical gripping tools costing thousands of dollars. However, the problem of managing weight transfers associated with tilting bottles for loading and unloading must still be dealt with. Problems multiply when it is desired to handle several bottles simultaneously, yet such handling is necessary if loading and unloading operations are to be cost efficient.
Consequently there is a need in the art for a device and method for loading and unloading bottles, which device could be used in conjunction with commercial industrial robots, lifting arms, mechanical lifts, or the like.
A method and apparatus are provided for manipulating a generally bottle shaped object, having a body and a neck, preferably with a mechanical arm. Thus an object engaging tool, controllably coupled to the mechanical arm using for example a coupling device may be positioned over the object while the object is resting in an upright position. A first contact surface of the object engaging tool engages the neck of the object on a first side thereof and a second contact surface engages the body of the object on a second side thereof opposite the first side. The second contact surface is preferably offset from the first contact surface such that the body of the object is engaged by the second contact surface at a point farther along a longitudinal axis associated with the object than the neck and on the opposite side thereof so as to establish a cantilever. The shape of the first contact surface further may generally conform to the cross section of a typical neck of the object, and the shape of the second contact surface may generally conform to the cross section of the body of a typical object.
Once positioned over the object, the position of the object engaging tool may be changed in a generally downward tilting manner so that the weight of the object is transferred to the engaging tool and may be supported between the first contact surface and the second contact surface in cantilevered relation. Accordingly, the object neck is cammed against the upper contact surface to securely support the object to facilitate movement thereof with the mechanical arm. The object may then be moved to a desired position by applying a lifting and translating motion to the mechanical arm.